1. Field of the Invention
The present invention relates to a multi-focal camera apparatus and methods and mediums for generating a focus-free image and an autofocus image using the multi-focal camera apparatus, and more particularly to a method, apparatus, and medium for generating a focus-free image and an autofocus image in which a plurality of images having different focal lengths can be captured by performing only one photographing operation, and then a focus-free image and an autofocus image can be generated based on the plurality of images.
2. Description of the Related Art
Due to recent developments in digital technology, digital devices have become light, compact, and slim. Also, with the growing trend to integrate a variety of digital devices, a mobile phone, a digital camera, and an MP3 player can be merged into a single digital device.
In general, the diameter of a lens of a camera phone, which is a mobile phone equipped with a digital camera, is less than that of a digital still camera (DSC). Thus, a camera phone has a wider depth-of-focus (DOF) range than a DSC. Since a typical camera phone has a DOF range between 60 cm and infinity, a relatively clear image of an object can be captured by a camera phone as long as the camera phone is at least 60 cm from the object. However, it is difficult to realize an autofocus function, which is one of the features of high-end digital cameras, in camera phones.
Even though camera phones generally have a relatively wide DOF range, they are likely to render objects other than an object located at a focal point blurry, even when the objects are about 60 cm apart therefrom. Accordingly, it is difficult to obtain focus-free images using camera phones. In addition, even if camera phones have a focal length greater than 60 cm, they are likely to render an object that is located at an object-side focal point with the highest sharpness, and render objects that are in front of or behind the object at the object-side focal point slightly blurry.